If you’ve had an AC Compressor fail on you, Murphy’s law states that it likely happened in the heat of the summer. Therefore you most likely want to get it fixed as soon as humanly possible. But WAIT! There are some critical steps to replacing your AC compressor that absolutely cannot be ignored.
If you are replacing the compressor in your vehicle these are a few critical steps that must be taken before installing a new compressor. These are not just suggestions, they are requirements. And your compressor warranty depends on it!
a) Clean your internals! In the case that the compressor has come apart internally, there is likely debris now scattered throughout the inside of your AC system. The place where the majority of this debris is usually collected is inside of the condenser. Many technicians prefer to replace the condenser when a compressor has come apart internally. This prevents the possibility of debris re circulating through the system and destroying your new compressor. Another option is to flush the condenser, hoses, and evaporator with a flushing solvent. A flush solvent can be bought at most auto supply stores to safely remove any debris located inside the system.
b) Unclog that tube. An AC system has one particularly vulnerable component that must be replaced when replacing a failed compressor. Depending on the type of system, your car either has an orifice tube, or an expansion valve. This component is the smallest part of the entire system that refrigerant must circulate through. It only takes the smallest piece of debris to block it and cause an inoperative AC system. That is why it is crucial to replace the orifice tube or expansion valve when replacing the compressor.
c) Keep it dry. ANY time you open the AC system is it important to replace the Drier or Accumulator (your car has one or the other depending on the type of your system). The drier and accumulator have a desiccant bag inside which removes any small amount of moisture that has introduced itself into the system. Moisture trapped inside the AC system can cause devastating effects to your new compressor, and can also reduce the efficiency of the system as a whole.
d) Lube it up. If the new compressor you are installing is not prefilled with oil, it is CRITICAL to refill the new compressor with the proper amount and type of oil. Refer to your service manual for your specific type and quantity of AC oil.
e) Suck it down. Prior to refilling your new system with refrigerant, it is very important to place a vacuum on the system. This will remove all air and moisture from the system so that only pure refrigerant is present when you refill the system. It is recommended to allow the system to be on a vacuum pump for at least an hour after the system has been opened.